I was looking at the spec sheets for Kodak Hi Def 400 this morning, and the information relating to grain size indicates that the grain is similar in size to Portra 400. I also looked at the spec sheets for Kodak color surveillance film (400 ISO) and it is identical to HD 400. However, it has additional information on exposure latitude and indicates that it can be pushed to ISO 800. Which indeed can Portra. I was wondering if anyone has tested HD400 or the surveillance stuff side by side with Portra 400. I know the former are only available as expired. But I am looking for a suitable film to stock up on for photographing small town fashion runway shows. Portra 400 is awesome, but mainly because of its pushability and fine grain. My hope is to find something equally pushable and with equally fine grain, but cheaper. Some of the surveillance stuff is available on the auction site. I generally only want to push to ISO 640, so even with a bit of speed loss that stuff may be OK. The grain is the main issue, other than cost.